So… got bored and threw in a Harmony H400a to my setup. When I would split my signal from the guitar and send it to both, the Recto would hum from a ground loop. I expected the same here, but there was not any hum at all. It won’t work for Metal, but for some good ol’ Classic Rock, Blues, or whatever isn’t brootuhl, it’s fun. The Mesa EQ actually sounds pretty good through the Harmony, but it’s very “middy” from the lack of lowest lows and highest highs due to an 8 inch speaker. At the right balance, it sounds great and provides some nice stereo sounds. If I were to ever get around to making the doodad to run the Harmony to a speaker cabinet, this would be awesome. If you have similar gear, it doesn’t hurt to try something and see if it makes a decent sound.